What is smpeg4 and is there a better way to convert then vcd?

[yoda313]

Ok what exactly is this codec?:



I'm downloading a bunch of videos and it seems like they are all encoded with this format. I can play them on my pc just fine. However I want to watch them on my tv. I have a ps3 and a xbox 360 and neither plays this natively. I also have the wd tv media player and it doesn't play it natively either.

These are rather low quality but watchable tv caps I'm watching so I don't need to convert to do mpeg2 or anything fancy. I ended up converting to plain old vcd (something I haven't done in a long time). The results have been suprisingly good given the source material.

My question is there a way to simply repatch this to behave as a divx or xvid without reencoding? I'm very pleased with the conversion time of tmpengc plus 2.5 on my dual core - I just finished an hour and half movie in 22 minutes to vcd mpg. However I'd like to be able to simply burn a cd or transfer straight to my usb drive for my wd tv media player rather than take the extra conversion time.

Would something like fourcc work on patching this to behave as a divx/xvid? Or am I not understanding what fourcc actually does?

And in the end is converting the best option for this type of a video file? I can live with the conversion time but if there is a quicker patch method I'd be interested. Thanks.

[Midzuki]

MP42 is <wiki>Non-standard MPEG-4 codec incompatible with the later standardized version of MPEG-4</wiki>

So forget about changing the fourcc bytes
Happy reencoding

[yoda313]

MP42 is <wiki>Non-standard MPEG-4 codec incompatible with the later standardized version of MPEG-4</wiki>

So forget about changing the fourcc bytes
Happy reencoding

@midzuki - oh man that sucks. Thanks for the info though.

I even ran into vbr audio on my last download. Fortunately I was able to demux the audio to wav and then encode it with the vcd video I did seperately with tda 2.0. I kept it as a pcm track so I had minimal reencoding time on the disc production side. I think it was about 10 minutes plus burn time. Give or take.

Well I guess this is a really old encode then huh?

I guess if I look at it an extra 22 minutes for a vcd mpg and then an extra 20minutes for a legit dvd (vcd with reencoded audio of course) that is a small price to pay.

Thanks again.

[jagabo]

ffdshow contains an MP42 decoder (An old Microsoft MPEG 4, part 2 codec. Theoretically the same as Xvid and DIvx. But as usual, Microsoft does everything their own, incompatible with the rest of the industry, way).

[Ai Haibara]

Yeah, but wasn't that the codec originally hacked to produce DivX 3? I don't remember how much of a difference there was between the Microsoft codec and DivX 3, though.

[Midzuki]

Yeah, but wasn't that the codec originally hacked to produce DivX 3? I don't remember how much of a difference there was between the Microsoft codec and DivX 3, though.

DivX 3 was based on MP43.
Maybe I'm wrong, but I doubt Xbox360 would support the MP4x codecs
even if these were wrapped in a .WMV file.

[jagabo]

ffdshow's MP42 decoder accepts both the fourcc MP42 and DIV2. So maybe an early version of Divx was based on MP42. Wikipedia says the first Divx was based on MP43 though.

[Ai Haibara]

Oh, okay. I just used to see people claiming it had been hacked from MP42, and took their word for it.

[yoda313]

Well ffdshow doesn't help me play it on a console or the wd media player. However maybe that is how I'm able to convert with tmpgenc 2.5 in the first place?

Thanks for all the insight everyone. I guess I'm just forced to convert these old encodes. That's ok as the output is fairly decent given the source material.

[jagabo]

Well ffdshow doesn't help me play it on a console or the wd media player. However maybe that is how I'm able to convert with tmpgenc 2.5 in the first place?

Yes. Enable the VFW MP42 decoder.

[yoda313]

@jagabo - I must have already done that previously on a seperate job some time ago. I have been encoding this way for the last few days since I've encountered this relic of a codec.

I appreciate the insight.

[jagabo]

I have some vague recollection of reading about a program that could convert MP42 to "normal" Divx without reencoding. ffmpeg maybe?

[yoda313]

Well I tried streaming the original avi to my ps3. Worked great! I used tversity and was able to get it going. Its only wifi g of course but this is standard def stuff so it was smooth. However it did tend to freeze up for a few seconds once or twice. Although I was downloading stuff at the time - would that interfere with the wifi streaming? It was on a computer in another room away from the ps3.

Anyway @ jagabo - thanks for the suggestion on ffmpeg. I'll take a look at it. Who knows.... That would be the most ideal to simply trick it into being a divx without reencoding. Would save a lot of time. Also I'm thinking of testing a conversion of a video into actual divx - though I might have problems with some of them that have vbr audio...